Eur. Phys. J. D (2014) 68: 13
https://doi.org/10.1140/epjd/e2013-40463-0

Regular Article

Quantum entanglement between amide-I and amide-site in Davydov-Scott model

¹ Department of Physics and Institute of Optics, Ningbo University, Ningbo 315211, P.R. China
² Institute of Physics, Chinese Academy of Sciences, Beijing 100190, P.R. China

^a e-mail: xtliang@ustc.edu

Received: 31 July 2013
Received in final form: 9 October 2013
Published online: 23 January 2014

Abstract

In this paper, we firstly derive non-Markovian operator Langevin equations of the Davydov monomer in its environment. Next, we replace the equations with the c-number quantum general Langevin equations (QGLEs) by calculating statistical and quantum averages of the operator Langevin equations. Then, by using the c-number QGLEs we investigate the evolutions of the subsystems amide-I and amide-site. The evolution of a parameter θ describing quantum entanglement of the coupling subsystems with continuous variable Hamiltonian has also been investigated. It is shown that there is certain entanglement between the amide-I and amide-site in the Davydov-Scott monomer.